[libvirt] [PATCH 1/2] Revert "util: vircgroup: pass parent cgroup into virCgroupDetectControllersCB"

[Pavel Hrdina]

This reverts commit 7bca1c9bdc85247446129f856e27c80a32819e17.

As it turns out it's not a good idea on systemd hosts.  The root
cgroup can have all controllers enabled but they don't have to be
enabled for sub-cgroups.

Signed-off-by: Pavel Hrdina <phrdina at redhat.com>
---
 src/util/vircgroup.c        |  2 +-
 src/util/vircgroupbackend.h |  3 +--
 src/util/vircgroupv1.c      |  3 +--
 src/util/vircgroupv2.c      | 17 ++++++-----------
 4 files changed, 9 insertions(+), 16 deletions(-)

diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c
index da506fc0b0..e4675a0977 100644
--- a/src/util/vircgroup.c
+++ b/src/util/vircgroup.c
@@ -407,7 +407,7 @@ virCgroupDetect(virCgroupPtr group,
 
     for (i = 0; i < VIR_CGROUP_BACKEND_TYPE_LAST; i++) {
         if (group->backends[i]) {
-            int rc = group->backends[i]->detectControllers(group, controllers, parent);
+            int rc = group->backends[i]->detectControllers(group, controllers);
             if (rc < 0)
                 return -1;
             controllersAvailable |= rc;
diff --git a/src/util/vircgroupbackend.h b/src/util/vircgroupbackend.h
index 1fe0851184..e58e327c68 100644
--- a/src/util/vircgroupbackend.h
+++ b/src/util/vircgroupbackend.h
@@ -95,8 +95,7 @@ typedef char *
 
 typedef int
 (*virCgroupDetectControllersCB)(virCgroupPtr group,
-                                int controllers,
-                                virCgroupPtr parent);
+                                int controllers);
 
 typedef bool
 (*virCgroupHasControllerCB)(virCgroupPtr cgroup,
diff --git a/src/util/vircgroupv1.c b/src/util/vircgroupv1.c
index 4231d8d6fa..7968ab3cf0 100644
--- a/src/util/vircgroupv1.c
+++ b/src/util/vircgroupv1.c
@@ -420,8 +420,7 @@ virCgroupV1StealPlacement(virCgroupPtr group)
 
 static int
 virCgroupV1DetectControllers(virCgroupPtr group,
-                             int controllers,
-                             virCgroupPtr parent ATTRIBUTE_UNUSED)
+                             int controllers)
 {
     size_t i;
     size_t j;
diff --git a/src/util/vircgroupv2.c b/src/util/vircgroupv2.c
index 502afb0b56..b3297dbb13 100644
--- a/src/util/vircgroupv2.c
+++ b/src/util/vircgroupv2.c
@@ -286,21 +286,16 @@ virCgroupV2ParseControllersFile(virCgroupPtr group)
 
 static int
 virCgroupV2DetectControllers(virCgroupPtr group,
-                             int controllers,
-                             virCgroupPtr parent)
+                             int controllers)
 {
     size_t i;
 
-    if (parent) {
-        group->unified.controllers = parent->unified.controllers;
-    } else {
-        if (virCgroupV2ParseControllersFile(group) < 0)
-            return -1;
+    if (virCgroupV2ParseControllersFile(group) < 0)
+        return -1;
 
-        /* In cgroup v2 there is no cpuacct controller, the cpu.stat file always
-         * exists with usage stats. */
-        group->unified.controllers |= 1 << VIR_CGROUP_CONTROLLER_CPUACCT;
-    }
+    /* In cgroup v2 there is no cpuacct controller, the cpu.stat file always
+     * exists with usage stats. */
+    group->unified.controllers |= 1 << VIR_CGROUP_CONTROLLER_CPUACCT;
 
     if (controllers >= 0)
         group->unified.controllers &= controllers;
-- 
2.21.0